I am finally in layout construction mode again as it gets further along, I'll need to be planning for power capacity to the rails in DCC operatoin.
The layout is planned to have:
- 1 approx 30' main yard with switching operations to local industries and engine facility.
- About 75 feet of mainline with two 20' passing sidings
- 1 staging yard with around 10 or 11 storage tracks.
Don't expect to be running more than 2 trains at a time most of the time, but occasionally up to 4 or 5. Most trains will have between 2 and 4 engines.
At present I have a Digitrax Radio Chief system with a 5 amp command station/booster. Assuming I stay with that system, how many 5 amp boosters/power districts would be needed to handle the layout? I may switch to a different system but I assume whatever system it is, will need to divide the layout into power districts each with a booster.
Off the top of my head, I'd guess at least a minimum of 3 power districts (main yard, mainline, staging yard) with 1 power booster each?
The layout room has two 15 amp circuits dedicated to the layout.
Rio Grande. The Action Road - Focus 1977-1983
In my view,what you already have should do the job no problem. You can create power districts with circuit breakers using the one 5 amp you already have. Adding a 5 amp booster to three districts is overkill and a waste of resources.
I agree. You generally need boosters for more engines, not more track. If you place your command station roughly in the middle of the layout and use good bus wires and feeders, the 5 amps you already have should suffice.
I do suggest subdividing with circuit breakers. This protects the layout better and allows shorts to be localized while the rest of the layout keeps running. N addition, if you feel the need for a booster in the future, the layout will already be broken up and insulated for it.
It takes an iron man to play with a toy iron horse.
riogrande5761 At present I have a Digitrax Radio Chief system with a 5 amp command station/booster. Assuming I stay with that system, how many 5 amp boosters/power districts would be needed to handle the layout? I may switch to a different system but I assume whatever system it is, will need to divide the layout into power districts each with a booster. Off the top of my head, I'd guess at least a minimum of 3 power districts (main yard, mainline, staging yard) with 1 power booster each?
Rich
Alton Junction
Your situation sounds similar to mine as regards number of trains and locos running at any given time during peak operations. So from that perspective, a booster might not be needed, and the single base station would be sufficient.
The reason I added a booster was because the length of the buss was getting close to or more than 40 feet from the centrally-located base station in either direction. The quarter test was failing at the extremes. By adding a booster, that issue was resolved, and as a bonus I was able to setup the booster as a reverser for the Wind River Canyon peninsula.
Robert
LINK to SNSR Blog
Two factors determien this. The main one is, how many traisn will run at a time. This straight up determins current requirements. Small layout, larger layout, simultaneously running 20 trains will need more than a single 5 amp booster, while no more than 5 trains running has PLENTY of power with 5 amps (unless it's O scale or larger).
Second, total size, mainly length of the power bus. There are diminishing returns from using bigger and bigger wire as the length grows, but you could run a very long bus with no voltage drop using #1 wire. But good luck attaching feeders to that, or pulling it under the benchwork. So the easier thing to do is add a booster, just to keep the bus length reasonable, even if the extra power isn't really needed.
25 feet is a common rule of thumb, using #12 wire. Putting the booster int he middle results in a total bus length of 50 feet. If the total is less than 100 feet, then divide it approximately in half, and then stick a booster in the middle of each half. ie, of the whole thing is 80 feet long, then you'd have the end of the bus, 20 feet of bus, a booster, 20 more feet of the same bus, then 20 feet of the second bus, booster #2, and then the last 20 feet of the second bus.
=====B1===== =====B2=====
It doesn't have to be precise by any means.
Within those to power distrits, adding circuit breakers to further divide things is always a good idea. With HO and smaller, no one loco needs a full 5 amps, and having half the layout stop dead because one loco runs a turnout and shorts is rather annoying.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
One thing I would suggest is to add toggle switches to your staging tracks. While the engines are not running, there's power going to them. One my railroad I have booster for my upper level, lower level which is staging, and my engine terminal. I agree with circuit breakers as others have suggested, I have them as well. I keep a lot of engines on the layout. I didn't mind splurging for the boosters. Just want my layout to have the power if need be.
Glad to see you're making progress!
Neal
In some of my NCE literature, it says you can run two post-1985 locos per amp with a bit of a safety margin built-in.
I used #12 buss wire because the place I bought it sold it to me way cheaper than the #14 he had. From my booster to the far reaches of my RR galaxy is about 30' each way from the booster. Rather than have a big loop of buss wire down and back making it 60', I used a terminal strip and sent out the buss wires like fingers.
Using the rule that everything must be soldered to something, meaning the rail must be soldered to a buss wire or to another rail that is soldered to a buss wire, I have never had an electrical issue in the twelve years I have been running this layout.
Brent
"All of the world's problems are the result of the difference between how we think and how the world works."
Neil do know. Yes, toggle switches to cut power feeds to blocks of staging has been suggested by some others as well and of course breakers. I do plan to have power cut off switches.
Three boosters I can understand may be overkill. One other person I was talking to thought a second booster may be good at the far end. There is 75 + helix feet of distance. I haven't calculated the number of turns in the helix vs radius to get the length of track there yet.
Also, on the few occasions that say, 4 trains are running with say 3 powered engines each, that is over the conservative 8 engines on a 5 amp booster suggested best practice.
Anyway, it's good news (less cost) that 3 boosters aren't really needed, but a 2nd one might be a good idea. It's a ways off before I need to do that but I'm trying to think ahead.
My layout uses four Digitrax 5 amp boosters for track power (And 15 PSX power/breaker districts). This number of boosters is largely predicated on the long runs required for the 10GA! track power bus wires. Even with four power boosters spread out around the layout there are still quite a few 35-40 foot runs for the main track power bus wires. I also have a 5 amp track power booster dedicated to turnout control/power. And I do not use the DCS-100 DCC controller for any track power, just DCC control.
So far this configuration has proven to be extremely resiliant.
Modeling an HO gauge freelance version of the Union Pacific Oregon Short Line and the Utah Railway around 1957 in a world where Pirates from the Great Salt Lake founded Ogden, UT.
- Photo album of layout construction -
riogrande5761Three boosters I can understand may be overkill.
Yeah but...
At MBK, the DB210 booster is $120. To implement your 3 power districts, you'll need at least 2 breakers. The PSX, which is most everybody's favorite, is $40 each. So if you buy a DB210 and 2 PSX's, you've spent $200. The DB220 Dual Booster is $170 (also MBK).
So your current booster + a DB220 can support your 3 power districts for $170 with 5 amps on one and up to 8 amps each on the other 2.
For $200 you can support 3 power districts, 1 at 5 amps and the 2 other sharing up to 8 amps.
It sounds like a no-brainer to me in favor of the DB220. Unless you decide you want more than 3 power districts. Then all bets are off.
BTW, some may argue that the PSX is a better breaker than the booster and they may be right. Unfortunately, that additional variable makes the calculation far too difficult for me.
And also BTW, booster amps for a layout are like horsepower in a car. I've never heard any car owner complain "I wish it had less horsepower".
I have the right to remain silent. By posting here I have given up that right and accept that anything I say can and will be used as evidence to critique me.
carl425 riogrande5761 Three boosters I can understand may be overkill. Yeah but... At MBK, the DB210 booster is $120. To implement your 3 power districts, you'll need at least 2 breakers. The PSX, which is most everybody's favorite, is $40 each. So if you buy a DB210 and 2 PSX's, you've spent $200. The DB220 Dual Booster is $170 (also MBK). So your current booster + a DB220 can support your 3 power districts for $170 with 5 amps on one and up to 8 amps each on the other 2. For $200 you can support 3 power districts, 1 at 5 amps and the 2 other sharing up to 8 amps. It sounds like a no-brainer to me in favor of the DB220. Unless you decide you want more than 3 power districts. Then all bets are off. BTW, some may argue that the PSX is a better breaker than the booster and they may be right. Unfortunately, that additional variable makes the calculation far too difficult for me. And also BTW, booster amps for a layout are like horsepower in a car. I've never heard any car owner complain "I wish it had less horsepower".
riogrande5761 Three boosters I can understand may be overkill.
Regarding the horsepower thing, another DCC person I got feedback from suggested actually less power by configuring a maximum of 2 or 3 ampes output and not using 5 amps. Reason being a short on a turnout with 4.5 amps and booster with 5 amps - if it doesn't switch off you could weld the engines wheels to the switch rails.
The suggested solution to that if I had a 5 amp booster would be to use a Digitrax PM-42. I'm told with it, the power can be set at different (and lower) levels for each power district. Say, set a district at 2 amps. One section might trip but the others keep going. PSX breakers can be used as well.
I've been advised to get a RRAmp meter and use it with the basic 5 amp system I have now to evaluate power demand. So before I look into additional boosters, like the scenary you suggested, I would need to see how much power is need and grow the system as necessary.
Doug/onewolf, dang! 10 AWG bus! Gnarley. I'd guess that 14 AWG for my rather much smaller layout may be sufficient, or 12 AWG at most.
Of course, consider the power supplies as well. Using MSRP because I don't feel like checking Modeltrainstuff right now, the DB210 uses the PS615, at $79 each. You'd need two.
The DB220, to get the full 8 amps out of each half, needs to use a PS2012E at $185.
So like usual, the higher power isn't always a cheaper alternative to two smaller units. Main reason STILL is that 5-6 amp power supplies are pretty much dime a dozen, it's a common rating for laptops. 8 amp and higher are not often used for anything and are more specialized.
And you shouldn't connect 8 amps directly to the rails for HO anyway.
riogrande5761 if it doesn't switch off you could weld the engines wheels to the switch rails.
I've heard this before. Has anybody seen any testing that's been done to determine where the line is? Your source seems to imply 4.5 amps will weld and 3 amps won't. I'm curious how we know that.
And on the 4.5 amp short not tripping the 5 amp breaker in the booster - this is why we use sufficiently large wire for our bus and feeders and do the quarter test. Regardless of how much power is available to the track a dead short MUST trip the breaker.
carl425 riogrande5761 if it doesn't switch off you could weld the engines wheels to the switch rails. And on the 4.5 amp short not tripping the 5 amp breaker in the booster - this is why we use sufficiently large wire for our bus and feeders and do the quarter test.
And on the 4.5 amp short not tripping the 5 amp breaker in the booster - this is why we use sufficiently large wire for our bus and feeders and do the quarter test.
I don't know but I'd prefer not to risk frying an expensive engine and the advise makes some sense. What is the quarter test?
Anyway, it sounds like I don't need to think about buying and additional boosters until I've tested the power demand using the RRAmp meter, and that is a ways off. Mainly I need to be breaking up the layout into multiple logical power districts and use PSX breakers - which I am not told can also be set up to limit amperage like the PM-42 (which I may not need if I don't have any reverse loops, which I don't).
riogrande5761What is the quarter test?
You lay a quarter across the rails at various points to make sure the breaker trips.
Whether it's 4.5 amps on a 5 amp breaker or 2.5 amps on a 3 amp breaker, if a short doesn't trip it, it's bad. The locomotive is not the only thing at risk. You're overheating the wiring and creating a fire hazard. Using less power does not eliminate the need for good wiring practice.
It's LESS likely that if the quarter test, done correctly (no cheating by pressing on the quarter!) passes everywhere ont he layout, that there would eb any issue. However, th booster does perioridically apply pwoer back to see if the short clears, so if you leave things long enough...
4.5 amps at a nominal HO voltage of 15 volts is 67.5 watts, so hotter than a 60 watt light bulb - can't touch one of those once it's on, and that can easily melt plastic (darn toddler age #1 son ruining my favorite Casio scientific calculator by 'hiding' it in a bedside lamp....). That's in part why I plan to set my circuit breakers to manual reset mode. 3 amps is 45 watts - my soldering station is only 40 watts.....
You can definitely find pictures of melted sideframes from locos that sat shorted out - in some cases even though the booster DID trip, it was that constant periodic reapplication of power that did it. Which is a good reason for another rule - don't leave things running when you leave the room.
rrinkerYou can definitely find pictures of melted sideframes from locos that sat shorted out
I've seen these before, but I've never seen loco wheels welded to the rail. Your 60-watt bulb is a good example, you can't touch it and it will melt plastic, but it's not going to melt NS rail and loco wheels.
Our club had a NCE five amp Power Pro and we wondered about enough power. Two rooms.
I built them a DCC amp meter using the below proven circuit and checked it with a surplus heavy duty rheostat. connected across the rails. Only for a few seconds. The booster finally tripped at about 4.8 amps as I recall some years ago.
We could run maybe eight to nine HO sound locos last I recall. Current was about 3.6 amps. We used the voltmeter option and the LED meter could be seen anywhere in the main room. A lot cheaper than the Rrampmeter.
The Harbor Freight meters a couple of us had showed about 13.6 vac for trouble shooting in case of track wiring issues.
http://www.circuitous.ca/DCCammeter10.html
If you ever fall over in public, pick yourself up and say “sorry it’s been a while since I inhabited a body.” And just walk away.
I just stumbled across this in the DB210/DB220 manual:
2.1 Number of Locos
Additional power districts may be needed to provide enough power to operate more locomotives than one power supply alone can handle. For example a 5 amp booster and power supply will operate between 10 and 15 average N-scale locomotives and between 6 and 10 HO locomotives. If you wish to run more locos on your layout, then you will need to set up more power districts to provide more total power.
Sounds about right. Depends on loco, but most modern non-sound locos would probably be best to not go above 8 from a 5 amp booster.
Sound loco's and lighed passenger cars will add to the load.
I ran 12 on my DCS50 Zephyr, rated at 2.5 amps. None was pulling a train though. I was just testing to see if the Zephyr had 10 or 12 slots. Advertised as 10, but it really has 12.
Some had sound, some didn't. I'd say 8-10 modern HO locos without sound is a conservative estimate for 5 amps.
I have two a command station/booster (DCS240) and a straight booster (DB100+) on the layout simply due to how the layout is arranged. The layout is essentially two different segments. The command station/booster controls one half and the booster runs the other half. Each booster has 6 circuit breakers that sub-divide the layout in to sub-districts so that if a short occurs, it doesn't take down the entire layout. I use all PSX breakers. They seem to fair better with my Tam Valley Frog juicers (only used on my main yard) and sound locomotives. I have had nothing but issues with the Digitrax PM-42's (on a club layout). We finally got rid of them and went to PSX breakers.
It is nice because the load is split on the layout. It may be overkill but I have never had a booster overheat or have a current load shutdown.
Colorado Front Range Railroad: http://www.coloradofrontrangerr.com/
So speaking of PSx breakers, I was chatting with a DCC vendor who suggested I consider the NCE EB1 breakers, which appear to be NCE's equivelent product to the DCC Specialties PSx. The gentelman suggested there were to reasons to consider the EB1 over the PSx. One is the cost was lower - their price was $10 less than the PSx. He also commented that the EB1 could be set as low as 2.5 amps for a trip point but the ESx would only go down to 3.x amps, maybe it was 3.5? He felt 2.5 amps was plenty of power for a power district and 3.5 was unnecessarily high.
Certainly food for thought, and if I break my RR into mulitple power districts and the EB1 does the job just as well, at $10 less per breaker, that could add up.
I do plan to use a number of Tam Valley Hex Frog Juicers and they are spect to operate between 2 and 5 amps IIRC. So either the PSx or EB1 would work, but being more econmical, the EB1 sound good.
The EB1 has nearly all of the features of the PSX. The PSX has some extra cost versions that add additional features but if you don't need that stuff... The EB1 has the most important one - adjustable trip, manual reset option, and remote LED indicator. The manual reset can even be a pushbutton OR using a turnout address. EB1 also has a graduated startup sequence, that can be programmed simiar to a speed table in a loco, so that it can reapply power in various time increments to allow keep alive capacitors to charge instead of instantly tripping as a short.
Even though you need 4x EB1's to equal a single PSX4 - divide the cost of the PSX4 by 4 and it's still more than the EB1. Plus you can shop around - most any NCE dealer will have the EB1 and can probably do a better price than Tony's. Remember that NCE has a MAP policy (minimum advertised price) so with many dealers you need to add the item to your cart to see the real price they are charging you. Oherwise it may look like ever dealer is selling their stuff for the same price.
I never had a problem with the PM42 on my previous layout even with multiple sound locos in the same section. No idea why some people. But they really aren't usable on a non-Digitrax system. ANd on my new layout I will need a lot more than one of them. EB1 is my top choice right now. Probably all using manual reset, too.
Yes, the vender I was talking to charges $37.95 for a single PSx but only $28.04 for the EB1. Thats essentially $10 cheaper. Yes, you can get PSx in 2's and 3's etc at a savings but the EB1 still comes out cheaper in similar quantities; that got my attention.
What are the extra cost versions additional feature that may be of note? Or is the standard PSx basically equivelent to the EB1?
Right now EB1 is looking like the winner between the two choices. Like the guy at the table with the sign: "EB1 over PSx, change my mind" LOL
BTW, how do you adjust the trip amperage on the EB1. Is it through a command station or computer interface? I think the PSx has a jumper you can use but I didn't see a jumper on the EB1 in the photo.
Either way with the EB1, but it has jumpers. The photos are less than clean, plus I think NCE supplies all the jumpers, or at least they are there in the photo - the unused ones hung off on one pin for storage, so it looks like a black rectangle in the photo but really it's the jumpers. Not everyone has a bag full of spare jumpers like I do from years of building computers back in the day when you had to manually set everythign with jumpers - RAM size, CPU speed, hard drive selection, etc. If you download the PDF manual for the EB1 from NCE< the picture on the first page of the instructiosn shows the jumpers pins with no jumpers, top center of the board, next to the large 6 pin IC. The hookup diagram on page 2 of the instructions has the EB1 flipped over end for end - the photo has the track conenction on the left and the input on the right, the wiring diagram shows it with the input on the left and track output on the right, so the jumpers are pictured on the bottom edge.
Current level is set with jumpers only, but there is a CV for trip time adjustment and another for how long it stays off before attempting to restart (or never, for manual reset mode). The instructions cover it all pretty well.
The PSX can be set as low as 1.27 amps, next stop is 3.8, 6.35 and 8.9 amps.
See Peter's post below
Henry
COB Potomac & Northern
Shenandoah Valley
rrinker Either way with the EB1, but it has jumpers. The photos are less than clean, plus I think NCE supplies all the jumpers, or at least they are there in the photo - the unused ones hung off on one pin for storage, so it looks like a black rectangle in the photo but really it's the jumpers. Not everyone has a bag full of spare jumpers like I do from years of building computers back in the day when you had to manually set everythign with jumpers - RAM size, CPU speed, hard drive selection, etc. If you download the PDF manual for the EB1 from NCE< the picture on the first page of the instructiosn shows the jumpers pins with no jumpers, top center of the board, next to the large 6 pin IC. The hookup diagram on page 2 of the instructions has the EB1 flipped over end for end - the photo has the track conenction on the left and the input on the right, the wiring diagram shows it with the input on the left and track output on the right, so the jumpers are pictured on the bottom edge. Current level is set with jumpers only, but there is a CV for trip time adjustment and another for how long it stays off before attempting to restart (or never, for manual reset mode). The instructions cover it all pretty well. --Randy
Either way with the EB1, but it has jumpers. The photos are less than clean, plus I think NCE supplies all the jumpers, or at least they are there in the photo - the unused ones hung off on one pin for storage, so it looks like a black rectangle in the photo but really it's the jumpers. Not everyone has a bag full of spare jumpers like I do from years of building computers back in the day when you had to manually set everythign with jumpers - RAM size, CPU speed, hard drive selection, etc.
If you download the PDF manual for the EB1 from NCE< the picture on the first page of the instructiosn shows the jumpers pins with no jumpers, top center of the board, next to the large 6 pin IC. The hookup diagram on page 2 of the instructions has the EB1 flipped over end for end - the photo has the track conenction on the left and the input on the right, the wiring diagram shows it with the input on the left and track output on the right, so the jumpers are pictured on the bottom edge.
Thanks for the additional info. I've built over 40 computers myself in past times and am familiar with jumpers on mother boards and hard drives etc. I may have some myself stashed away but I've moved many times so things tend to fall away with successive moves. Anyway, hopefully NCE would supply the needed jumpers with their EB1 breaker.
I forget most companies have instruction manuals in PDF form on their website.
BigDaddy The PSX can be set as low as 1.27 amps, next stop is 3.8, 6.35 and 8.9 amps.
Good to know. My discussion with the DCC shop guy makes sense with that. Since the Tam Valley Frog Juicer reportedly needs a minimum (from memory) of 2 amps, the lowest setting on the PSx would not be useful. The next step up being 3.8 is what the DCC guy felt was rather high and why he felt the 2.5 amp setting on the EB1 was preferable and plenty sufficient for most needs. From what others have been commenting, that seems to be true.
So if you had multiple EB1's set at 2.5 amps, the 5 amp booster could supply several districts more than addequately potentially. I do intend to get an RRAmp meter to monitor power usage as well to see if I even need an additional booster or not.
If I do need an additional booster, the Tam Valley TV Booster looks like an economical way to do that AND it includes breaker built in so an additional separate breaker may be superflous. The TV booster provides 3 amp continuous and 5 amp peak for as low as about $43 which ain't bad.